10  *  : add quick-buffer for sload compression support
64 			*offset -=  in __get_device_fd()
69 	return -1;  in __get_device_fd()
81 /* ---------- dev_cache, Least Used First (LUF) policy  ------------------- */
88 static uint64_t *dcache_lastused; /* last used ticks for cache entries */
113 	20, -20, 40, -40, 80, -80, 160, -160,
114 	320, -320, 640, -640, 1280, -1280, 2560, -2560,
123 	/* Number of used cache entries */  in dcache_print_statistics()
130 	 *  c: number of cache entries  in dcache_print_statistics()
133 	 *  CH: cache hit  in dcache_print_statistics()
134 	 *  CM: cache miss  in dcache_print_statistics()
135 	 *  Repl: read cache replaced  in dcache_print_statistics()
176 		return -1;  in dcache_alloc_all()
184 		return -1;  in dcache_alloc_all()
218 	/* release previous cache init, if any */  in dcache_init()
230 	/* halve alloc size until alloc succeed, or min cache reached */  in dcache_init()
249 static inline char *dcache_addr(long entry)  in dcache_addr()  argument
251 	return dcache_buf + F2FS_BLKSIZE * entry;  in dcache_addr()
254 /* relocate on (n+1)-th collision */
255 static inline long dcache_relocate(long entry, int n)  in dcache_relocate()  argument
258 	return (entry + dcache_relocate_offset[n]) %  in dcache_relocate()
266 	long entry, least_used, target;  in dcache_find()  local
270 	target = least_used = entry = blk % n; /* simple modulo hash */  in dcache_find()
274 			return target;  /* found target or empty cache slot */  in dcache_find()
277 		target = dcache_relocate(entry, try); /* next target */  in dcache_find()
282 /* Physical read into cache */
283 static int dcache_io_read(int fd, long entry, off64_t offset, off64_t blk)  in dcache_io_read()  argument
285 	if (pread64(fd, dcache_buf + entry * F2FS_BLKSIZE,  in dcache_io_read()
288 		return -1;  in dcache_io_read()
290 	dcache_lastused[entry] = ++dcache_usetick;  in dcache_io_read()
291 	dcache_valid[entry] = true;  in dcache_io_read()
292 	dcache_blk[entry] = blk;  in dcache_io_read()
297  *  - Note: Read/Write are not symmetric:
298  *       For read, we need to do it block by block, due to the cache nature:
300  *       For write, since we always do a write-thru, we can join all writes into one,
301  *       and write it once at the caller.  This function updates the cache for write, but
303  *  - Note: We concentrate read/write together, due to the fact of similar structure to find
304  *          the relavant cache entries
305  *  - Return values:
307  *       1: cache not available (uninitialized)
308  *      -1: error
329 				(size_t)(F2FS_BLKSIZE - addr_in_blk));  in dcache_update_rw()
330 		long entry = dcache_find(blk);  in dcache_update_rw()  local
335 		if (dcache_valid[entry] && dcache_blk[entry] == blk) {  in dcache_update_rw()
336 			/* cache hit */  in dcache_update_rw()
337 			if (is_write)  /* write: update cache */  in dcache_update_rw()
338 				memcpy(dcache_addr(entry) + addr_in_blk,  in dcache_update_rw()
343 			/* cache miss */  in dcache_update_rw()
347 				if (dcache_valid[entry])  in dcache_update_rw()
349 				/* read: physical I/O read into cache */  in dcache_update_rw()
350 				err = dcache_io_read(fd, entry, start, blk);  in dcache_update_rw()
356 		/* read: copy data from cache */  in dcache_update_rw()
359 			memcpy(buf, dcache_addr(entry) + addr_in_blk,  in dcache_update_rw()
366 		byte_count -= cur_size;  in dcache_update_rw()
373  * dcache_update_cache() just update cache, won't do physical I/O.
374  * Thus even no error, we need normal non-cache I/O for actual write
376  * return value: 1: cache not available
377  *               0: success, -1: I/O error
384 /* handles read into cache + read into buffer  */
398 		return -1;  in dev_read_version()
433 				return -ENOMEM;  in sparse_write_blk()
485 		return -ENOMEM;  in sparse_merge_blocks()
532 	/* err = 1: cache not available, fall back to non-cache R/W */  in dev_read()
533 	/* err = 0: success, err=-1: I/O error */  in dev_read()
538 		return -1;  in dev_read()
575 	 * dcache_update_cache() just update cache, won't do I/O.  in dev_write()
576 	 * Thus even no error, we need normal non-cache I/O for actual write  in dev_write()
579 		return -1;  in dev_write()
581 		return -1;  in dev_write()
593 		return -1;  in dev_write_dump()
611 		return -1;  in dev_fill()
613 		return -1;  in dev_fill()
640 			return -1;  in f2fs_fsync_device()
653 			return -1;  in f2fs_init_sparse_file()
658 			return -1;  in f2fs_init_sparse_file()
661 		c.device_size &= (~((uint64_t)(F2FS_BLKSIZE - 1)));  in f2fs_init_sparse_file()
665 		MSG(0, "\tError: Corrupted sparse file\n");  in f2fs_init_sparse_file()
666 		return -1;  in f2fs_init_sparse_file()
672 		return -1;  in f2fs_init_sparse_file()
678 		return -1;  in f2fs_init_sparse_file()
685 	return -1;  in f2fs_init_sparse_file()
718 		int64_t chunk_start = (blocks[0] == NULL) ? -1 : 0;  in f2fs_finalize_device()
731 			if (chunk_start != -1) {  in f2fs_finalize_device()
732 				if (j - chunk_start >= MAX_CHUNK_COUNT) {  in f2fs_finalize_device()
734 							j - chunk_start, 0);  in f2fs_finalize_device()
736 					chunk_start = -1;  in f2fs_finalize_device()
740 			if (chunk_start == -1) {  in f2fs_finalize_device()
755 						j - chunk_start, 0);  in f2fs_finalize_device()
763 				chunk_start = -1;  in f2fs_finalize_device()
766 		if (chunk_start != -1) {  in f2fs_finalize_device()
768 						blocks_count - chunk_start, 0);  in f2fs_finalize_device()
780 	 * in the block device page cache.  in f2fs_finalize_device()
792 			MSG(0, "\tError: Failed to close device file!!!\n");  in f2fs_finalize_device()